.demo-grid .demo-case .bh-col{
    margin-bottom: 20px;
    line-height: 24px;
    text-align: center;
    color: #FFF;
}
.demo-grid .demo-case .bh-col:nth-child(2n+1){
    padding: 16px 0;
    background-color: rgba(0,146,255,.75);
}
.demo-grid .demo-case .bh-col:nth-child(2n){
    padding: 16px 0;
    background-color: #0092ff;
}

.demo-grid .demo-case2 .bh-col:nth-child(3n+1){
    height: 60px;
    line-height: 60px;
    padding: 0;
    background-color: rgba(0,146,255,.75);
}
.demo-grid .demo-case2 .bh-col:nth-child(3n+2){
    height: 50px;
    line-height: 50px;
    padding:  0;
    background-color: #0092ff;
}
.demo-grid .demo-case2 .bh-col:nth-child(3n){
    height: 40px;
    line-height: 40px;
    padding:  0;
    background-color: #0092ff;
}